Full authority digital engine controls (FADECs) are well known systems used to automatically control the performance of an aircraft engine. A separate FADEC is typically associated to each one of the engines of the aircraft. Typically, each FADEC has two (or more) fully functional and independent ‘channels’ which provide redundancy to each other to maintain engine performance control in the event of an individual channel failure.
Each channel thus typically has some form of engine control unit (ECU) (sometimes referred to as electronic engine controller—EEC) and related accessories which control the aspects of aircraft engine performance. In short, the ECU receives data (e.g. air density, throttle lever position, engine pressures/temperatures), processes the data, determines any adjustments to be made to controlled engine parameters, and controls the engine parameters (e.g. fuel flow, vane position) accordingly.
In many modern FADECs applications on multiple engine aircrafts, buses are provided to allow communication between channels of different engines and each engine can receive data concerning operating conditions of the other engine(s) via the associated bus and this latter data is included in the processing operation to optimize engine control parameters.
Although FADECs and their associated buses provided communication which was satisfactory to a certain degree, there remains room for improvement. In particular, it was desired to improve overall communication throughput and/or reduce time delays of the communications between engine FADECs whilst retaining redundancy and fault tolerance to single point failures.